1. Field of the Invention
The present invention generally relates to a vehicle capable of whole-wheel steering. More particularly, the invention relates to a riding-astride type whole-wheel steered vehicle on which a driver rides astride.
2. Description of Relevant Art
In Japanese Patent Application Lay-Open Print No. 59-192685, laid open on Nov. 1, 1984, there is disclosed a riding-astride type whole-wheel steered vehicle including a vehicle body frame, front wheels attached through a front axle to the front part of the vehicle body frame, rear wheels attached through a rear axle to the rear part of the vehicle body frame, a midship engine mounted on the vehicle body frame between the axles in the longitudinal direction of the vehicle, a power transmission mechanism for transmitting power of the engine to at least either of the front and rear axles, a handle member and a driver's seat disposed on the vehicle body frame, left and right footsteps attached to the vehicle body frame at both sides of the engine, respectively, a front-wheel steering mechanism for interconnecting the handle member with the front wheels and steering the front wheels, a rear-wheel steering mechanism for steering the rear wheels, and a steering transmission mechanism for mechanically interconnecting the front-wheel steering mechanism with the rear-wheel steering mechanism. This vehicle is intended for off-road travelling and thus has contrivances made such as the low-pressure type balloon tires are employed for the front and rear wheels.
In the vehicle above, however, both the power and steering transmission mechanisms are disposed at one side of the engine, whereby the freedom in design of the vehicle body frame is restricted, resulting in an increased cost.
Moreover, in the vehicle above, which is of a riding-astride type, the power and steering transmission mechanisms are needed to be arranged within a transverse distance between the left and right footsteps. In this respect, to thus arrange both of the transmission mechanisms at one side of the engine, the transmission mechanisms are required to be disposed one above the other. As a result, in order to ensure the vehicle level to be higher than predetermined relative to the ground, either of the transmission mechanisms is disposed at a relatively high position.
With such points in mind, the present invention has been achieved to effectively solve problems in conventional riding-astride type whole-wheel steered vehicles.